code: def _lgamma_cpu(x, dtype):
      from scipy import special
  
      return numpy.vectorize(special.gammaln, otypes=[dtype])(x)
  
file_path: chainer/tests/chainer_tests/functions_tests/math_tests/test_lgamma.py
imports: import unittest
  import numpy
  import chainer
  from chainer import backend
  from chainer.backends import cuda
  import chainer.functions
  from chainer import testing
label_desc: Use image node_id 1 for calling a global function with example usage: _lgamma_cpu(x, dtype) and returns: numpy